
That thought is now behind me, for I've found a quick peventive remedy

3/16 rope caulk (Ace Hardware) used for sealing old windows. Just roll it thin between your fingers and press it into the groove of the floorboard where the cover sits. It's non-permanent and can be easily scraped out. Off course, it will probably require a screwdriver to pry up the cover. It has a clay-like consistancy.